WERTHEIMER: Now that the Supreme Court has upheld most of the health care law, the Affordable Care Act, the action turns to the states.

Each state has two big tasks: first is deciding whether to take federal money to expand Medicaid.

MONTAGNE: States are supposed to provide Medicaid to a larger base: people making incomes up to 133 percent of the poverty level, just under $15,000 a year.

WERTHEIMER: That means Medicaid expands to about 17 million additional people. If states do agree to expand their coverage, the federal government will pay most of the cost for the newly eligible people.

MONTAGNE: States also face a requirement to implement a health insurance exchange. That's a website to help consumers shop for and purchase health plans.

This morning, we have a tale of threes states.

WERTHEIMER: We begin in Mississippi, where the health care ruling could put some of the poorest people in the poorest state in a bind. That state is already building an online health insurance marketplace, but some lawmakers say they are reluctant to expand the Medicaid eligibility.

JEFFREY HESS, BYLINE: Mississippi has been working for months to build a health insurance exchange. Under the law, if the state does not set one up, the federal government will. So even though Mississippi challenged the federal health law, the state's Republican Insurance Commissioner Mike Chaney has actually been pushing hard to get an exchange in place.

MIKE CHANEY: It is important to us that we take care of the citizens of this state, that we have an exchange designed by Mississippians for Mississippians and operated by Mississippians and not by the federal government. We do not think that one-size-fits-all is the right way to go. What will work in New York State or California may not work in Mississippi.

HESS: Some estimate that 275,000 Mississippians will be eligible for the exchange. But the future of those adults who don't make enough money to enter the exchange is more murky.

Many of them would be eligible for the expanded Medicaid program. But the price may be too much to bear, says Mississippi Governor Phil Bryant, who thinks the state should consider opting out of the Medicaid expansion.

GOVERNOR PHIL BRYANT: We'll certainly seek opportunities that the state might have to reduce the welfare cost to Mississippians. If you look at adding 400,000, that literally would damage this budget beyond repair.

HESS: The state's lieutenant governor has also indicated that the state should opt out, warning that the expansion could cost close to $2 billion. Other estimates put the price tag at a fraction of that amount, closer to $400 million. Some Democrats and other supporters of the expansion argue it could bring more economic stability to the state's health care market.

Roy Mitchell with the Mississippi Health Advocacy Program thinks politicians are cherry-picking the highest possible cost estimates to oppose the expansion.

ROY MITCHELL: State lawmakers and policymakers should be looking at the impact and the benefits. The increased state cost that Mississippi will have to pay to expand Medicaid will be largely, if not completely, offset by the new federal funding and its related spinoffs by the reductions in uncompensated care costs.

HESS: The Mississippi Hospital Association also supports an expansion, saying hospitals cannot be expected to treat so many people with no hope of being paid. It predicted, without the expansion, hospitals would be forced to close, leaving many Mississippians in the lurch.